1. Field of the Invention
This document generally relates to a display apparatus, and more particularly, to a plasma display apparatus and a driving method thereof.
2. Discussion of Related Art
In general, a plasma display apparatus of a display apparatus has a plasma display panel, and a driver for driving the plasma display panel.
In general, a plasma display panel has a front panel and a rear panel. A barrier rib formed between the front panel and the rear panel forms one discharge cell. Each cell is filled with an inert gas containing a primary discharge gas, such as neon (Ne), helium (He) or a mixed gas of Ne+He, and a small amount of xenon (Xe).
A plurality of the cells form one pixel. For example, a red (R) discharge cell, a green (G) discharge cell, and a blue (B) discharge cell form one pixel.
In the plasma display panel constructed above, when the inert gas is discharged with a high frequency voltage, it generates vacuum ultraviolet rays. Phosphors formed between the barrier ribs are excited to display images.
The plasma display panel constructed above can be made thin and light, and has thus been in the spotlight as the next-generation display devices.
A plurality of electrodes, such as a scan electrode Y, a sustain electrode Z, and an address electrode X, are formed in the plasma display panel. A predetermined driving voltage is applied to the plurality of electrodes to generate a discharge, whereby images are displayed.
A driver Integrated Circuit (IC) for supplying the driving voltage to the electrodes of the plasma display panel is connected to the electrodes.
For example, a data driver IC can be connected to the address electrode X of the electrodes of the plasma display panel, and a scan driver IC can be connected to the scan electrode Y of the electrodes of the plasma display panel.
A thing comprising the plasma display panel in which a plurality of electrodes are formed and a driver for supplying a predetermined driving voltage to the plurality of electrodes of the plasma display panel, as described above, is called a “plasma display apparatus”.
In this case, an exemplary structure of the plasma display apparatus comprising the related art data drive IC for supplying the driving voltage to the address electrode X of the plasma display panel will be described below with reference to FIG. 1.
FIG. 1 is a view illustrating an exemplary structure of a plasma display apparatus having a data drive IC in the related art.
Referring to FIG. 1, the plasma display apparatus in the related art comprises top switches Qt1, Qt2, Qt3 and bottom switches Qb1, Qb2, and Qb3, which are connected in series between a data voltage source (not shown) for supplying a data voltage Vd and a base voltage source (not shown) for supplying a base voltage GND, respectively.
Address electrodes X of the plasma display panel are connected between the top switches Qt1, Qt2, and Qt3 and the bottom switches Qb1, Qb2, and Qb3.
Each of the top switches Qt1, Qt2, and Qt3 and each of the bottom switches Qb1, Qb2, and Qb3 form one data drive IC.
In other words, the top switch Qt1 and the bottom switch Qb1 form a data drive IC (reference numeral “100”). The data drive IC of reference numeral “100” is connected to the address electrode Xa of the plurality of address electrodes X of the plasma display panel.
In this manner, a data drive IC (reference numeral “101”) is connected to an address electrode Xb, and a data drive IC (reference numeral “102”) is connected to an address electrode Xc.
Meanwhile, it has been shown in FIG. 1 that the number of the data drive ICs comprised in the related art plasma display apparatus is three. However, the number of the data drive ICs may be varied depending on the number of the address electrodes X.
The operation of the plasma display apparatus in the related art will be described below with reference to FIG. 2.
FIG. 2 illustrates an operating timing diagram illustrating the operation of the plasma display apparatus in the related art.
Referring to FIG. 2, if the top switch Qt1 of the data drive IC 100 is turned on in the address period, the data voltage Vd from the data voltage source (not shown) is supplied to the address electrode Xa through the top switch Qt1. Accordingly, a voltage of the address electrode Xa rises up to Vd and is then kept, as shown in FIG. 2.
Thereafter, if the top switch Qt1 of the data drive IC 100 is turned off and the bottom switch Qb1 of the data drive IC 100 is turned on, the voltage of the address electrode Xa becomes a base voltage GND. That is, the top switch Qt1 and the bottom switch Qb1 alternately operate to supply the address electrode Xa with a data signal of the data voltage Vd.
The switching operation for supplying the data signal may be applied to the data drive IC 101 and the data drive IC 102 in the same manner.
In the related art plasma display apparatus operating as described above, switching elements used for each data drive IC as shown in FIG. 1 must have a relatively high withstanding voltage characteristic.
For example, it is assumed that a magnitude of the data voltage Vd supplied by the above-mentioned data voltage source (not shown) is 60V and a resistance value of each of the top switches Qt1, Qt2, and Qt3 is R.
In this case, when the data voltage Vd is supplied to the address electrode Xa through the data drive IC (reference numeral 100 of FIG. 1), a current flowing through the top switch Qt1 and a magnitude of power consumed in the top switch Qt1 can be expressed in the following equation 1.i=60V/R W=i×60V  [Equation 1]
Here “i” denotes a magnitude of current flowing through the top switch Qt1, and “W” denotes a magnitude of power consumed in the top switch Qt1.
From Equation 1, it can be seen that the above-mentioned top switch Qt1 consumes power of i×60V when being driven.
At this time, heat is generated from the top switch Qt1 in proportion to the consumption power W.
For example, assuming that the resistance value R of the top switch Qt1 is 30Ω (ohm), heat of (60/30)×60=120 W is generated from the top switch Qt1.
In summary, the top switch Qt1 must have a withstanding voltage characteristic enough to withstand heat generated according to power of i×60V.
As described above, the switching elements with a relatively high withstanding voltage characteristic are expensive. Accordingly, a problem arises in that the production cost of the plasma display apparatus becomes further high.
More particularly, in the case of a specific pattern in which, for example, picture data are repeated between logic values 1 and 0, excessively high heat is generated from the top switch Qt1. Accordingly, there is a problem in that damage, such as the burning of the top switch Qt1, occurs.